Ruben Amorim has warned Manchester United forward Marcus Rashford that he "has to change" if the unsettled star wants to save his Old Trafford career.
Rashford has not played for United since a Europa League tie against Viktoria Plzen in December after Amorim made the shock decision to drop him for his team's Premier League victory at Manchester City.
The 27-year-old will miss his 12th successive game when Amorim's side finish the Europa League group phase at Romanian outfit FCSB on Thursday.
Rashford said he was ready for a "new challenge" after being axed for the City clash.
And although he trained with his teammates on the eve of the match, he was again omitted from the squad as fourth-placed United bid to avoid a play-off tie by booking automatic qualification for the last 16.
Amorim said after United's Premier League win at Fulham last weekend that he would rather have the club's 63-year-old goalkeeping coach in his squad than Rashford in a damning take on the England star's commitment to the cause.
Rashford has been linked with AC Milan and Barcelona among other clubs and, asked on Wednesday, if there was any update on the situation, Amorim made it clear the forward would have to change his attitude to get back in the team.
"The last time I talked about that in the last game, my sentence was that I will not put in any player that don't give the maximum," he said.
"When I feel that it is the right moment, I will put any player to play and, I will say it again, we are a better team with Marcus Rashford. And that is clear. He is a big talent.
"But until the right moment, I will not change my mind. That's all, and it's always the same answer."
- 'Nothing against Marcus' -
With Monday's transfer deadline looming, Amorim would clearly like to resolve the Rashford situation, but few clubs offer an obvious landing spot due to his hefty wages.
"You can look at our team and imagine the profile of the players," Amorim said.
"Now imagine a talent like Rashford. Our team should be so much better with Rashford, but he has to change. If he does change, we are more than welcome to put a talent like Rashford in, and we need it.
"But in this moment I think it's really clear that we have to set some standards. That's all. We are waiting for Marcus if he wants it really bad. That's the only thing.
"You try to make like something personally is behind it. It's not. I have nothing against Marcus.
"I just have to make the same rules for everybody, and that, for me, is so simple. It's always the same answer."
After a rocky start to his reign, Amorim hopes United can finish in the Europa League top eight.
That would secure progress to the last 16 without a play-off round, giving Amorim more time to work with his spluttering team on the training pitch.
"It's massive for us. We can have two weeks without any game in the middle of the week, and that in this moment is really important," he said.